patch 9.1.0216: Error on exit with EXITFREE and 'winfixbuf'

Problem:  Error on exit with EXITFREE and 'winfixbuf'.
Solution: Handle DT_FREE before checking for 'winfixbuf'.
          (zeertzjq)

closes: #14314

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    216,
 /**/
     215,
 /**/